Cleaning of the interior of tubes, specially applicable for cleaning condenser tubes



R 8 o 9 F l E 9 WI L P P A Y Tu L A I C E P S CARR 2 Sheets-Sheet 1 M 9 R E1 M m ww M m l Mi A F E L c CLEANING OF THE INTERIOR OF TUBES,

April 29, 1924'.

9 bl-a OHrne7 r CIALLY APPLICABLE FOR 2 Shepts-Sheet 2 SPE TUBE 923 DENSER '1, l

E. CARR OF TUBES,

CON M8.

RIOR NG Filed CL A I CLEANING OF THE 1 April 29 1924.

Patented Apr. 29, 1924 PATENT if ALFRED EDWARD CARR, 015 BLACKI-IEATH, LONDON, ENGLAND.

CLEANING OF THE INTERIOR 0F TUBES,

SPECIALLY APPLICABLE FGB CLEANING CONDENSER TUBES.

Application filed May 1,

To all whom it may concern:

Be it known that I, ALFRED EDWARD CARR, a subject of the King of Great Britain, and resident of Blackheath, London S. E/ 3, England, have invented certain new and useful Improvements in and Relating to the Cleaning of the Interior of Tubes, Specially Applicable for Cleaning Condenser Tubes, of which the following is a speciio fication.

This invention relates to an improved means of cleaning the interiors of tubes from any deposit. The invention is particularly applicable to cleaning the interiors of tubes of surface condensers. At the pres-' ent time it is usual to clean the interiors of such tubes by means of wire brushes but the process is very tedious and further is not altogether satisfactory. Also it has been proposed to clean such tubes by means of steam and also by compressed air, but neither of these media is satisfactory in itself.

According to this invention, I propose to clean the interiors of tubes, such as those of surface condensers, by means of a jet of *hot wet air which is projected through the tube at a considerable velocity, the action completely and instantly clearing away any deposit or dirt without any liability of distorting or drawing the tubes. Preferably, the injection of hot wet air through the tube is effected by the use of a tube cleaner device consisting of-one or more steam jets, which by an ejector action entrain and deliver through a nozzle a volume of air which becomes saturated with moisture from the condensed steam from the jet and is projected through the nozzle into each tube in turn at a high velocity. 'It is found that an application for a few seconds of such a saturated air jet is sufficient to clean out the tube, the time and expense thus required for cleaning a fairly large condenser being very considerably reduced.

Apparatus in accordance with this invention is illustrated in the accompanyin drawings in which Fig. 1 is a longitudina section through the cleaner, Fig. 2 being a fragmentary longitudinal section in a plane at right angles to Fig. 1. Fig. 3 is a cross section on the line A'A, Fig. 1, and Fig. 4 is an end view of Fig. 1 looked at from the left. I I

The apparatus shown comprises an outer block 6.

1923. SerialNo. 635,972.

barrel 1 at the front end of which is posi-' tioned a delivery nozzle 2 for the hot wet air, this nozzle, when the apparatus is being used, being inserted into the bore of the condenser tubesor the like to be cleaned. Apertures 3 forming air inlets are provided either in the barrel 1 itself or .in an end disc-41 of the barrel into which disc the delivery nozzle 2 is screwed. Fitted at the rear of the nozzle 2 is a throat tube 5 shaped in the manner of an injector tube. At the rear of the barrel 1 is fixed a boss or block I 6 to a cavity 7 in which. the steamsupply is led by way of a branch 8. In the interior of the block 6: is slidably mounted a tube 9, the rear end of which is fitted with a cap 10 forming a valve seat 11 and normally closing an aperture 12 in the valve seat through which the steam from the cavity 7 passes when the valve is opened. The tube 9 at its forward end terminates in a jet13 axial with the outer barrel, and this jet 13 and the tube 9 vare carried on a spider 14.- which is connected to' the handle 16 by rods 15 sliding in recesses in the A spring 17 tends normally to press the block and the handle 16 apart and thus close the valve 10 on its seating. The spring 17 is shown disposed round the rear stem of a casing 18 which screws into the end of the block 6 and holds the valve seating 11 in. position. In the shellof this casing 18 are two sets of ports .19 and 20, and in thetube 9 are two other sets of ports 21, 22. A plug 23 is screwed into the front end of the block 6 and retains a washer or disc 24: in the block which acts as a paclring for the sliding tube 9. The interior of the plug 23, see Fig. 2, is hollow and forms the aperture 12, round the annular clearance 25 in the-block 6 and through the apertures 21 to the interior of the tube 9; the apertures 2-2 being masked by the disc 24 due to the slight forward movement of the tube 9. Steam is, therefore, blown through'the nozzle 1.3 and forms withthethroat tube 5 an injector inducing a flow of air by way of the apertures and interior of the barrel 1 into the throat tube 5; the air and steam being propelled out through the nozzle 2. This is the primary action as the handle 16 is initially pushed in, the air flow being first started by the action of the jet 13. I

As the handle moves further in the ports 22 pass to the left of the packing disc 24 and communicate with the cavity 25'" in the plug 23, consequently, the steam now passes through the annular recess 25 through. the ports 21 and out by way of the ports 22 to the cavity 25, in the plug 23, the steam now ialso issuing from the jets 26 as well as from the nozzle 13. This is the secondary action when the handle 16 has been pushed in to its full extent, an increased injector effect along the tube 5 being now set up by the twin jets 26. Although two jets 26 have been described and shown a series of such jets might be provided.

When dry or superheated steam is caused to issue from jets in the usual way it behaves more or less as a perfect gas, and the jet of issuing steam takes up a constant formation the central stream in such a jet being practically useless for driving air along, as only the outer surface of the jet comes into con tact with the air, and in an apparatus such as that shown air would only be forced down the throat tube 5 by the wedging action, so to speak, of the steam jet 13. By providing the outer jets 26, however, a better propulsive effect on the air is obtained. In order further to augment this propulsion, instead of the steam issuing in a continuous stream it is caused to issue from all the jets in a series of puffs, such puffs not only wedg ing the air into the throat 5 but acting in the manner of pistons positively to propel it forward. Again owing to the cold air, entrained by the injector action of the steam passing round the exterior of the throat tube 5 the steam is deliberately saturated and the globules of moisture with which the wet steam is charged tend to interfere with the shape of the issuing steam jet, the globules also acting as floating pistons and tending positively to propel the air forward.

In order to obtain an interrupted action on the steam issuing from the jets a piston valve 27 is mounted slidably in the casing 18, such valve having a series of angled ports 28 com municating from the rear wall of the valve to its periphery and'an axial hole 28. When, therefore, steam passes from the cavity 7 through the ports 19 and the aperture 12 it also acts on the left hand end of the valve 27 and blows the latter back in the casing to the right, this action bringing the angled ports 28 opposite the second series of ports 20 in the casing 18 and permitting steam to pass through the angled ports to the rear of the valve '27 and as the. pressure on this rear face will be higher than that obtaining against the opposite end face due to the steam flowing quickly away from that end face by way of the aperture 12, the valve 27 will be blown to the left shutting off the aperture 12 and also the ports 28 until the pressure again accumulating in the now sealed cavity at the left hand end of the casing 18 forces the valve 27 to the right, and so on, this action continuing and causing the steam to issue from the jets in a series of puffs. Instead of this reciprocating valve, an interrupter effect may be obtained by the posing a rotating fan wheel in the path of the steam.

As the air is entrained through the outer barrel 1 such barrel or sheath remains comparatively cool, even when using steam at a high velocity.

It will be seenthat primarily the steam enters the tube 5 only from the nozzle 13, a slight delay action taking place before the steam subsequently issues fromthe nozzles 26.

By reason of the delayed action mentioned, the induced air flow is set up by the primary steamjet quietly and smoothly without any liability of a blow back occurring. This feature is of great importance asthe mechanism needs to be operated 'many thousands of times in cleaning out a large condenser. As the apparatus is removed from'the tube and pressure is taken off the handle the spring recloses the main valve 10 and shuts off the supply.

The operation of the main valve and the action of the jets is thus accomplished automatically by merely pressing the apparatus against the tube to be cleaned, and steam cannot be blown back against the operator, as might occur if independent valve mechanisms had to be controlled by him or he failed to shut ofithe steam when withdrawing the tube cleaner.

I claim:

1. Apparatus for cleaning the interior of tubes comprising, an outer barrel, a Valve seating formed in a block fixed in theprimary jet tube, a valve controlling the steam supply to the jets, an operating handle connected to the valve and slidable in the block, the initial movement of the handle to open the valve admitting steam by way of one series of ports to the primary jet, further movement admitting steam also by way of the other series-of ports to the cavity and the secondary jets.

2. Apparatus for cleaning the interior of tubes comprising, an outer barrel, a throat tube within said barrel, a jet delivering steam to the throat tube in such manner as 'to entrain air from the barrel into the tube by an injector action, a casing in the outer barrel, a piston valve slidable in the casing, and controlling the admission of steam from the casing to the jet, two sets of steam inlet ports to the casing, one set admitting steam to the jet and the interior of the casing 011 one side of the piston valve the other set being controlled by the piston valve and adapted to admit steam to the other side of the piston valve by way of ports in said valve, and said ports in the valve, whereby the valve is reciprocated and intermittently opens and closes the steam supply to the jet.

In testimony whereof I affix my signature in presence of two witnesses.

Witnesses:

W. PRESS, A. L. ROSE. 

